Ueber das Kohlensuboxyd. I

Diels, Otto; Wolf, B.

doi:10.1002/cber.190603901103

Cited by 109 publications

(60 citation statements)

References 2 publications

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“…15,16 Crystallographic studies have also provided direct evidence of energetically and structurally significant interactions between CAO groups and arene rings 9 ; in all these cases the carbonyl group points toward the centroid of the aromatic ring at distances in the range of 2.8 -3.2 Å. Interestingly, the corresponding stabilizing interactions give reason of specific molecular geometries. 9,11 Following our previous studies on the reactivity of carbon suboxide, C 3 O 2 , 17,18 with suitable stabilized phosphorus ylides, which yielded bis-ylidic derivatives of malonic acid, 19 we have obtained new molecules producing self-assembled networks in the solid state.…”

Section: Introductionmentioning

confidence: 98%

Further crystallographic evidence of NH� � �? (system) and CO� � �? (system) interactions: The structures of bis(diarylhydrazonecarbonyl)methylene derivatives [{ArPhC?NNH?C(O)}2CH2] (Ar = Ph, 2-C5H4N, 2-C4H3S)

Ganis¹,

Valle²,

Pandolfo³

et al. 1999

Biopolymers

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Section: Introductionmentioning

confidence: 98%

Further crystallographic evidence of NH� � �? (system) and CO� � �? (system) interactions: The structures of bis(diarylhydrazonecarbonyl)methylene derivatives [{ArPhC?NNH?C(O)}2CH2] (Ar = Ph, 2-C5H4N, 2-C4H3S)

Ganis¹,

Valle²,

Pandolfo³

et al. 1999

Biopolymers

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“…Tetraaminoallenes (TAAs) have therefore been termed as "hidden" carbones. [4,5] We also calculated complexes of AuCl with carbon suboxide, C 3 O 2 [29] (6), as ligand, which is usually written with double bonds O=C=C=C=O. [29b,c] It has been shown that carbon suboxide, which has a quasi-linear equilibrium geometry with a remarkably shallow bending potential, [30] may also be seen as carbodicarbonyl C(CO) 2 .…”

Section: Introductionmentioning

confidence: 99%

Distinguishing Carbones from Allenes by Complexation to AuCl

Esterhuysen

Frenking

2011

Chemistry A European J

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Quantum chemical calculations have been performed for the dicoordinated carbon compounds C(PPh(3))(2), C(NHC(Me))(2), R(2) C=C=CR(2) (R = H, F, NMe(2)), C(3)O(2), C(CN)(2)(-) and N-methyl-substituted N-heterocyclic carbene (NHC(Me)). The geometries of the complexes in which the dicoordinated carbon molecules bind as ligands to one and two AuCl moieties have been optimized and the strength and nature of the metal-ligand interactions in the mono- and diaurated complexes were investigated by means of energy decomposition analysis. The goal of the study is to elucidate the differences in the chemical behavior between carbones, allenes and carbenes. The results show that carbones bind one and two AuCl species in η(1) fashion, whereas allenes bind them in η(2) fashion. Compounds with latent divalent carbon(0) character can coordinate in more than one way, with the dominant mode indicating the degree of carbone or allene character. The calculated structures of the mono- and diaurated tetraaminoallenes (TAAs) reveal that TAAs exhibit a chameleon-like behavior: The bonding situation in the equilibrium structure is best described as allene [(R(2)N)(2)]C=C=C[(NR(2))(2)] in which the central carbon atom is a tetravalent C(IV) species, but the reactivity suggests that TAAs should be considered as divalent C(0) compounds C{C[(NR(2))(2)]}(2), that is, as "hidden" carbones. Carbon suboxide binds one AuCl preferentially in the η(1) mode, whereas the equilibrium structures of the η(1)- and η(2)-bonded diaurated complex are energetically nearly degenerate. The doubly negatively charged isoelectronic carbone C(CN)(2)(2-) binds one and two AuCl very strongly in characteristic η(1) fashion. The N-heterocyclic carbene complex, [NHC(Me)(AuCl)], possesses a high bond dissociation energy (BDE) for the splitting off of AuCl. The diaurated NHC adduct, [NHC(Me)(AuCl)(2)], has two η(1)-bonded AuCl moieties that exhibit aurophilic attraction, which yield a moderate bond strength that might be large enough for synthesizing the complex. The BDE for the second AuCl in [NHC(Me)(AuCl)(2)] is clearly smaller than the values for the second AuCl in doubly aurated carbone complexes.

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“…In homonuclear 13 C doublequantum filtered NMR only pairs of 13 C atoms give rise to 1 The spin system of the three nuclei from 13 C-C 3 O 2 after polymerization will be isolated from the next nearest 13 C spins for statistical reasons. The spin system of these three nuclei will be linear in the sense that only one carbon atom is directly bound to the two others.…”

Section: Resultsmentioning

confidence: 99%

“…An explanation for the absence of the peaks at 150 and 163 ppm in the 2D triple-quantum spectrum is straightforward. 1 Information about the coupling partners of the nucleus behind the observed triple-quantum filtered resonance can be reconstructed from the observed resonance frequencies in the indirect dimension. The triplequantum coherence is evolving under the sum of the chemical shifts of the contributing spins in the indirect dimension, meaning that the resonance frequencies can be predicted from the 1D spectrum.…”

Section: Resultsmentioning

confidence: 99%

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The Structure of Poly(carbonsuboxide) on the Atomic Scale: A Solid‐State NMR Study

Günne

Beck

Hoffbauer

et al. 2005

Chemistry A European J

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In this contribution we present a study of the structure of amorphous poly(carbonsuboxide) (C3O2)x by 13C solid-state NMR spectroscopy supported by infrared spectroscopy and chemical analysis. Poly(carbonsuboxide) was obtained by polymerization of carbonsuboxide C3O2, which in turn was synthesized from malonic acid bis(trimethylsilylester). Two different 13C labeling schemes were applied to probe inter- and intramonomeric bonds in the polymer by dipolar solid-state NMR methods and also to allow quantitative 13C MAS NMR spectra. Four types of carbon environments can be distinguished in the NMR spectra. Double-quantum and triple-quantum 2D correlation experiments were used to assign the observed peaks using the through-space and through-bond dipolar coupling. In order to obtain distance constraints for the intermonomeric bonds, double-quantum constant-time experiments were performed. In these experiments an additional filter step was applied to suppress contributions from not directly bonded 13C,13C spin pairs. The 13C NMR intensities, chemical shifts, connectivities and distances gave constraints for both the polymerization mechanism and the short-range order of the polymer. The experimental results were complemented by bond lengths predicted by density functional theory methods for several previously suggested models. Based on the presented evidence we can unambiguously exclude models based on gamma-pyronic units and support models based on alpha-pyronic units. The possibility of planar ladder- and bracelet-like alpha-pyronic structures is discussed.

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Ueber das Kohlensuboxyd. I

Cited by 109 publications

References 2 publications

Further crystallographic evidence of NH� � �? (system) and CO� � �? (system) interactions: The structures of bis(diarylhydrazonecarbonyl)methylene derivatives [{ArPhC?NNH?C(O)}2CH2] (Ar = Ph, 2-C5H4N, 2-C4H3S)

Further crystallographic evidence of NH� � �? (system) and CO� � �? (system) interactions: The structures of bis(diarylhydrazonecarbonyl)methylene derivatives [{ArPhC?NNH?C(O)}2CH2] (Ar = Ph, 2-C5H4N, 2-C4H3S)

Distinguishing Carbones from Allenes by Complexation to AuCl

The Structure of Poly(carbonsuboxide) on the Atomic Scale: A Solid‐State NMR Study

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